//全局变量
a = 10
var b = 20
a = b = 15
console.log(a)
//局部变量
let c = 30
c = 33
console.log(c)
//局部常量 使用关键字const 一般常量名全部大写
console.log(Math.PI)


const AGE = 60
console.log(a, b, c, AGE)
console.log(typeof (a), typeof (b), typeof (c), typeof (AGE))


